Check your Windows ISO image

All SHA1 signatures for Windows 7 installation DVDs

Introduction

Installation DVD for the Windows 7 operating system are available as an ISO image file from various sources on the web.
This ISO file must be burned on a writable DVD that can be then used to install Windows 7 on a computer.
Before doing this, it is important that you check the integrity of the ISO file and that it has not been tampered with.

If an ISO image file has been tampered with, this can mean that some trojan or virus has been added to the image.
Beware that some online shops are selling very cheap Windows licenses and installation ISO files.
The reason behind this very low price could be that they want you to install an infected version of Windows, to later take control of your computer.

So the goal of this web page is to give you the procedure to check the integrity of the ISO file, so you can then be sure that your Windows installation is safe.

Disclaimer

This site doesn't contain any illegal content.
It doesn't contain any Windows 7 ISO file, nor any link to Windows 7 ISO files.
It contains only a compilation of SHA1 signatures, which is an information that is publically available on various Microsoft's websites.

What is a SHA1 signature or hash?

SHA1 is a cryptographic algorithm that is applied to all the bytes of a file.
The output of that algorith is a 40-byte signature also called a hash or checksum.
Altering the file content, even a single bit, will results in a totally different signature.
So if the computed signature of the ISO image in your hands matches the one published by Microsoft and listed below, you can be 100% sure that every bit of your file is identical to what Microsoft has published and that no one has tampered with the image.

How to check a SHA1 signature?

Several free tools are available to compute SHA1 signatures.
Their usage is very simple and similar from one tool to the other.
Basically after launching the tool, you browse for the Windows 7 ISO image file from a file dialog and then the tool computes automatically the SHA1 signature.
This will take some time as the ISO images are quite big and the SHA1 algorithm is quite complex.

One of the easiest tool to use for the casual user is the "MD5 & SHA1 Checksum Utility" from Raymond Lin.
It is a free, lightweight and "portable" tool, i.e. it doesn't need to be installed.
Just download the .exe file from Softpedia here and launch it.
An easy user interface opens, browse for your ISO file and wait for the SHA1 signature to be displayed.

If you prefer to use a command line tool, you can download one directly from Microsoft here.
To compute the SHA1 signature for your ISO image file, in a command console type : fciv.exe -sha1 <filename of the ISO>.

You will find below the original name of each ISO file as well as the corresponding SHA1 signature.
The exact name of your image can be different depending of the distribution channel, this is not critical as long as the SHA1 matches one listed.

You can also reduce the length of the list by clicking on the "filters" button.
This can also be used to select other ISO images not currently displayed (other languages or other special distributions such as "VL", N" or "KN", etc).

Currently displaying Windows 7 versions in arabic and hebrew languages.